So to summarise it looks to me like the way to go is:
Gem all Agi, unless there is a nice bonus for yellow, in which case Agi+Mastery.
Reforge all haste to Mastery.
If there is no haste to reforge, reforge hit/exp/crit in that order.
Ench Agi/Mastery.

I hope things change for cata, otherwise gearing looks a bit linear.

Your summation is correct. Another viable approach is to simply reforge the highest stat on a given item to gain the highest amount of mastery possible although this method won't work for everyone since maintaining critical strike >50% is nearly mandatory. The closer you are to the critical strike soft cap the more carefully you should balance critical strike against expertise and hit.

Please note that there aren''t (to my knowledge) any mastery gems or enchantments available on live as yet.

Mihir will likely provide a new breakdown once Cataclysm is released.

The gear for Cataclysm looks nice but you won't, initially at least, be doing 30,000 dps even in full Tier 11 or equivalents and all possible raid buffs. Balancing stats in Cataclysm may be quite different as well especially since 50% critical strike is theoretically impossible even with all possible raid buffs given the known equipment thus far.

also to figure out what stats to reforge, what should my crit and haste be around? is there a set number? or straight priority as mentioned above?

Ideally, assuming you are well geared then you would want the following:

critical strike until you reach the expertise and hit suppression point for melee attacks (or 76% if expertise and hit capped)
haste near 20% but no specific goal just reforge a lot of haste into mastery try not to drop much lower than 20%
upon reaching those goals you should carefully balance critical strike, expertise and hit

i get an error message in the picture box when trying to load the picture in Mew. any tips? i am using a mac and i know i have java enabled.
AKA how do i configure my computer to accept the mew

Are you using the installer or the web version?
Which version of OS X? OS X 10.6.4?
Which version of Safari? Safari 5.0.2?
Which version of Java VM are you using? Java 1.6?
Are you blocking pop-ups?
Are you accepting self-signed .jars?

also i am trying to get mew to work but i dont know how to configure my computer to do so. i have java and a mac but i just get error messages when i load the page.

thanks for the help!

Please see my questions below about your configuration in relation to Mew. Mew is platform neutral so it should function. If all else fails you may go here and start a thread to which Yawning or Tangedyn, the developers, may respond.

Unfortunately, your Armory isn't updated and Armory doesn't support mastery or reforging as yet. It sounds like you could give up some expertise or hit for more mastery or agility.

yes, the accept/deny thing doesnt reappear/ ill have to figure out how to accept it again

i reforged 1 piece of gear with expertise because i was at 32 exp.
the other was just a crit and i went down 1%. but i wanted the full extra point in mastery. i for some reason dont have a lot of haste. maybe gem a bit haste and reforge gear haste to mastery?

yes, the accept/deny thing doesnt reappear/ ill have to figure out how to accept it again

i reforged 1 piece of gear with expertise because i was at 32 exp.
the other was just a crit and i went down 1%. but i wanted the full extra point in mastery. i for some reason dont have a lot of haste. maybe gem a bit haste and reforge gear haste to mastery?

In your situation you need to look at reforging other stats into mastery. Start reforging some of the critical strike, expertise and hit into mastery. Do not gem for critical strike, expertise or hit. The exception is getting your meta gem activated

For Mew, perhaps try going into security (located in system preferences).
Click the firewall tab followed by the advanced button down the bottom.
Check all the applications you want are set to allow incoming connections.
Close security preferences.
Then open a finder window Navigate to -> Macintosh HD -> Library -> there will be a file called, com.apple.alf.plist delete it, reboot and your done.
Deleting this small file re-builds the Firewall preferences and you will no longer be asked to accept incoming network connection every time you open an app.

I ponder how much Haste you would have to have in order to make Energy regeneration noticeably faster, and how much to make that beneficial for getting more attacks off in X seconds.
Probably an unobtainable amount I'm guessing.

I ponder how much Haste you would have to have in order to make Energy regeneration noticeably faster, and how much to make that beneficial for getting more attacks off in X seconds.
Probably an unobtainable amount I'm guessing.

In fact, 20% is relatively noticeable. Approximately 655 Haste is equivalent to ~20% increased energy regeneration which equates to ~ 2 Shreds additional every 30 seconds according to my calculations.

In my trials, 40% haste was barely manageable especially with Tiger's Fury or Berserk. With 50% haste I felt as if I permanently had the Berserk effect and with Tiger's Fury or Berserk I couldn't spam abilities fast enough so a lot of energy was wasted.

If you want to know how much crit rating you can afford with your current level of agility, hit rating and expertise rating, you should make sure you're in caster form and unbuffed. Start with 76, substract your % hit and % expertise, then substract the agility on your char sheet multiplied by 0.1324. The resulting value you multiply by 45.93, and that's how much crit rating you would need to hit the crit cap.